Help ! Memory allocating problems

[Virender Kashyap]

Hi,
    I am working on a small implementation in gcc-code. I declare some
data structures, using GTY(()) tag ..and allocate elements using 
ggc_alloc_cleared function.
To free data, i use ggc_free function.
       The problem is that many a times i get strange memory allocation 
segfaults in xcalloc/xmalloc. In case i don't free any allocated memory, 
things work fine most of the times.
           What could be the problem above. Also what is the correct method 
of allocating and dealloction of data/arrays in gcc ?
          Please help as i am already bugged by these errors :(, and this 
is urgent for my project.

Thanks and Regards,
Virender